Frequency of vacA, cagAand babA2virulence markers in Helicobacter pyloristrains isolated from Mexican patients with chronic gastritis

Paniagua Gloria, Monroy Eric, Rodríguez Raymundo, Arroniz Salvador, Cristina Rodriguez, Cortés José, Camacho Ausencio, Vaca, Negrete Erasmo, Vaca Sergio

Description

Helicobacter pylori has been strongly associated with chronic gastritis, peptic and duodenal ulcers, and it is a risk factor for gastric cancer. Three major virulence factors of H. pylori have been described: the vacuolating toxin (VacA), the cytotoxin-associated gene product (CagA) and the adhesion protein BabA2. Since considerable geographic diversity in the prevalence of H. pylori virulence factors has been reported, the aim of this work was to establish the H. pylori and vacA , cagA and babA2 gene status in 238 adult patients, from a marginal urban area of Mexico, with chronic gastritis. Methods H. pylori was identified in cultures of gastric biopsies by nested PCR. vacA and cagA genes were detected by multiplex PCR, whereas babA2 gene was identified by conventional PCR. Results H. pylori -positive biopsies were 143 (60.1%). All H. pylori strains were vacA + ; 39.2% were cagA + ; 13.3% were cagA + babA2 + and 8.4% were babA2 + . Mexican strains examined possessed the vacA s1, m1 (43.4%), s1, m2 (24.5%), s2, m1 (20.3%) and s2, m2 (11.9%) genotypes. Conclusion These results show that the Mexican patients suffering chronic gastritis we have studied had a high incidence of infection by H. pylori . Forty four percent (63/143) of the H. pylori strains analyzed in this work may be considered as highly virulent since they possessed two or three of the virulence markers analyzed: vacA s1 cagA babA2 (9.8%, 14/143), vacA s1 babA2 (4.9%, 7/143), and vacA s1 cagA (29.4%, 42/143). However, a statistically significant correlation was not observed between vacAs1 , cagA and babA2 virulence markers (χ 2 test; P > 0.05).

Informations

• Publié par: biomed
• Publié le: 01 janvier 2009
• Nombre de lectures: 22
• Langue: English

Extrait

Annals of Clinical Microbiology and Antimicrobials

BioMedCentral

Open Access Research Frequency ofvacA,cagAandbabA2virulence markers in Helicobacter pyloristrains isolated from Mexican patients with chronic gastritis 1 12 Gloria Luz Paniagua, Eric Monroy, Raymundo Rodríguez, 1 12 Salvador Arroniz, Cristina Rodríguez, José Luis Cortés, 2 11 Ausencio Camacho, Erasmo Negreteand Sergio Vaca*

1 Address: Facultadde Estudios Superiores Iztacala, Universidad Nacional Autónoma de Mexico, Avenida de los Barrios 1, Los Reyes Iztacala, 2 Tlalnepantla, 54090, Estado de Mexico, Mexico andHospital General Regional 72 del Instituto Mexicano del Seguro Social, Av. G. Baz s/n, Tlanepantla, 54000, Estado de Mexico, Mexico

Email: Gloria Luz Paniagua  [e-mail]; Eric Monroy  [e-mail]; Raymundo Rodríguez  [e-mail]; Salvador Arroniz  [e-mail]; Cristina Rodríguez  [e-mail]; José Luis Cortés  [e-mail]; Ausencio Camacho  [e-mail]; Erasmo Negrete  [e-mail]; Sergio Vaca*  [e-mail] * Corresponding author

Published: 30 April 2009Received: 12 February 2009 Accepted: 30 April 2009 Annals of Clinical Microbiology and Antimicrobials2009,8:14 doi:10.1186/14760711814 This article is available from: http://www.annclinmicrob.com/content/8/1/14 © 2009 Paniagua et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract Background:Helicobacter pylorihas been strongly associated with chronic gastritis, peptic and duodenal ulcers, and it is a risk factor for gastric cancer. Three major virulence factors ofH. pylori have been described: the vacuolating toxin (VacA), the cytotoxinassociated gene product (CagA) and the adhesion protein BabA2. Since considerable geographic diversity in the prevalence ofH. pylorivirulence factors has been reported, the aim of this work was to establish theH. pyloriand vacA,cagAandbabA2gene status in 238 adult patients, from a marginal urban area of Mexico, with chronic gastritis. Methods:H. pyloriwas identified in cultures of gastric biopsies by nested PCR.vacAandcagAgenes were detected by multiplex PCR, whereas babA2 gene was identified by conventional PCR. + Results:H. pyloripositive biopsies were 143 (60.1%). AllH. pyloristrains werevacA; 39.2% were + ++ + cagA; 13.3% werecagA babA2and 8.4% werebabA2. Mexican strains examined possessed the vacA s1, m1(43.4%),s1, m2(24.5%),s2, m1(20.3%) ands2, m2(11.9%) genotypes. Conclusion:These results show that the Mexican patients suffering chronic gastritis we have studied had a high incidence of infection byH. pylori. Forty four percent (63/143) of theH. pylori strains analyzed in this work may be considered as highly virulent since they possessed two or three of the virulence markers analyzed:vacA s1 cagA babA2(9.8%, 14/143),vacA s1 babA2(4.9%, 7/143), andvacA s1 cagA(29.4%, 42/143). However, a statistically significant correlation was not observed 2 betweenvacAs1,cagAandbabA2virulence markers (χtest; P > 0.05).

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